Fig. 3: The mechanism of the dimension transitions.

a PL transitions during the dimension transition process and corresponding molecular reassembly diagram. b The liquid-state 1D ¹H NMR spectra of TAI and TAI-PbI₂ in deuterated ACN. c 1D selective NOESY spectra with titration of D₂O in deuterated ACN. d Schematic diagram of the molecular packing changes during the dimension transition process based on SXRD results. e Surface morphologies of A-1D tablet, 1D/2D tablet and F-1D tablet. After cycles of dimension transitions, the F-1D tablet with no microstrain and pinholes is fabricated. f Contact angles characterization of TA-based perovskite tablets. F-1D tablet exhibits a larger water contact angle of 110.6°. g Cross-section SEM images of the TA-based perovskite tablets. The F-1D perovskite tablet represents a compact bulk with no pinholes, while the A-1D perovskite tablet shows many irregular holes. h Hardness of classical 3D MAPbI₃, 2D PEA₂PbI₄, all-inorganic Cs₂AgBiBr₆, and TA-based perovskite tablets.